RT Journal Article
T1 El desarrollo de la Capa de Arroyofrío (límite Calloviense-Oxfordiense) al Sur de Zaragoza, entre Ricla y Aguilón: bioestratigrafía y facies
T1 On the lateral extent of the Arroyofrío Bed (Callovian-Oxfordian boundary) between Ricla and Aguilón (south ofZaragoza; Iberian Range, Spain): biostratigraphy and facies
A1 Meléndez Hevia, Guillermo
A1 Ramajo Cordero, Javier
A1 Martínez Cotanda, R.
AB New biostratigraphic data on the Middle-Upper Jurassic (i.e. Callovian-Oxfordian) boundary bed (the socalled:Arroyofrío Bed), at the South of Zaragoza (NE Iberian Range) show that the Callovian-Oxfordianboundary is located at the base of this irregular stratigraphic interval. Both the facies and fossil content of thebed (ammonites, belemnites, brachiopods, bivalves, crinoids, stromatolite structures and planktic foraminifera)are indicative of marine sedimentary conditions. However, the revision of biostratigraphic data, as well astaphonomic analysis, confirm the presence of a basin-extent stratigraphic and registratic gap involving atleast the upper Lamberti and Mariae zones. Taphonomic features shown by ammonite internal moulds, suchas disarticulation surfaces, truncation surfaces, phosphate infilling, and in some cases ellipsoidal abrasionfacets and annular furrows, are evidence of taphonomic reelaboration. The latter abrasion features indicatethat ammonite reelaborated moulds stood for long time on the sea bottom after being exhumed and wereabraded by the action of shallow directional currents under extremely shallow intertidal to even supratidalconditions, resulting in a probable widespread sub aerial exposure of the platform. All this supports thehypothesis of the boundary bed being formed in punctuated sedimentary events during lower and, mostprobably, early middle Oxfordian. These data are of primary importance to understand the palaeogeographicsetting of the northeastern Iberian Platform at the turn of Middle-Upper Jurassic
PB Sociedad Geológica de España
YR 2005
FD 2005
LK http://hdl.handle.net/10272/8712
UL http://hdl.handle.net/10272/8712
LA spa
DS Repositorio Institucional de la Universidad de Huelva
RD 1 jun 2026